51% attack is one of the worst nightmare in crypto space. The aim of decentralisation is to bring transparency, trustworthy and privacy .But every project cannot be a full sucess. Being decentralised in nature still there is high risk of attack from mining community in any crypto project which is term as 51% attack. The main reason behind is the decentralisation, where is no backup or control from any organisation or centralised authority. Hence people with more mining power have higher chance to undergo 51% attack.
What is a 51% attack
Inorder to stay as decentralised a seperate algorithm called proof of work(POW) and proof of stake(POS) is used. For this people needs expensive equipment like GPU, ASICS and many other mining equipment inorder to mine crypto. But since its hard to buy all those equipment and also require lots of maintenance, decentralisation is necessary. Where people can mine according to their own capability forming groups or community.
But in doing this if any group or people are able to hold 51% of the whole mining power for extended period of time then this could lead to double spend . This is called 51% attack in crypto space.
Double spend is the process of reversing the previous transaction allowing it to spends the same currency for two or more transactions. This prevent or block any upcoming new trasaction from other people .
Reasons behind 51% attack
51% attack is all about how much mining power people can affort. And how much hashrate can be rent. Here is the list of reason behind 51% attack
- Decentralisation
One of the basic reason behind 51% attack is decentralisation where mining power is given to individual without any rule or control from any authority or oganisation. Hence individuals or group which can afford more mining power can achieve the attack easily.
- Renting of hashrate
Renting of hashrate become easier this days. Hence the project which rent higher hashrate gets higher chance from 51% attack
- Forked
Fork is one of the loophole in crypto space which could lead to 51% attack. Since it used the same mining algorithm as its original crypto. Hence we can see maximum 51% attack on bitcoin fork.
- Low value and maximum supply
In crypro space any crypto with low and underated value are prone to 51% attack. This is mainly because crypto project which are new and have low value in market require less hashrate for mining.hence it will require only a few expences to achieve a 51% attack making is less secure. One example is the 51% attack on bytecoin. Which occur three time within a period of 1 week.
- Introduction of mining farms
With the introduction of mining farm the number of 51% attack case has increased. This can be mainly due to the present of bugs inside the program making it less secure.
How to prevent from 51% attack
51% attack can be achieved on those crypto project which have low mining hashrate, low mining expenses, higher renting percentage of hashrate etc
It is hard to make a 51% attack on Bitcoin because of its rules and algorithm behind the project. In bitcoin there are rule on how many BTC can be mined per block whic are followed by all the nodes in the network. So when a new block is produced after holding majority of mining power other nodes will reject the block making it invalid. Hence preventing from 51% attack. Another way is increasing the hashpower and cost of hashrate per hour. Just like in bitcoin since the cost of hashrate perhour is very high it will require a quite high amount of expenses in order to achieve 51% attack .Above all introducing new consensus algorithm can also be a new means of preventing the 51% attack.
List of top 10 crypto project less prone to 51% attack
List of crypto project more prone to 51% attack
Conclusion
Despite of all this a 51% attack is possible in real world and this is mainly prone to those project which are very young in the market and have very low hashrate . This attack mainly occurs on altcoin family which lack good market opportunities and low underated value. But more secure to bigger project like Bitcoin, ethereum etc
